﻿Currents and Temperatures in Gulf of St. Lawrence. 55 



have also to be taken into account. Wind, as we know, 

 influences currents. On Lake Ontario, it will, when 

 blowing down the lake continuously for some time even 

 pile up the water at the lower end to a height of many 

 inches and create underneath a reverse current. The 

 direct effects produced by winds are, however, not 

 relatively deep, and, therefore, probably hardly have a 

 perceptible influence upon any cold current in the Gulf 

 which underlies warmer waters. Thus in the Straits of 

 Belle Isle, at a depth of thirty to forty fathoms, a 

 high wind from the west may have but little effect on a 

 current from the east. Again, although the great mass of 

 water in the ocean as well as in the land-locked Gulf of 

 St. Lawrence, is swayed backward and forward twice each 

 day, the whole moves together, and it is quite possible to 

 conceive of the currents in these bodies of water main- 

 taining their directions irrespective of the motion of the 

 whole mass, of which these currents form only a part, with 

 different causes for their motion. The rise and fall of the 

 surface, which is the popular notion of the tide, is, Prof. 

 G. H. Darwin has, among other matters, pointed out to 

 me, really the outcome of a small current in the whole 

 fluid, the current being reversed in direction every twelve 

 hours. The subject has an important bearing on the 

 existence of a more or less continuous cold current 

 inwards at the Straits of Belle Isle. The cold current, if 

 it exists at all there, as a definite factor, is to be sought 

 for more as a deep seated than even a surface current, 

 and will be found clinging to the northerly side of 

 the Straits where the deepest channel is also known to 

 exist. How far does the effect of the tide there at forty 

 to fifty fathoms seriously interrupt such a current ? It is 

 in this northern part of the Straits where investigations 

 into the undercurrents are still wanted. Mr. Dawson's 

 observations, where they were made outside of the three 

 miles distance from the Labrador coast, show that some 



